1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _ASM_X86_NOPS_H |
3 | #define _ASM_X86_NOPS_H |
4 | |
5 | #include <asm/asm.h> |
6 | |
7 | /* |
8 | * Define nops for use with alternative() and for tracing. |
9 | */ |
10 | |
11 | #ifndef CONFIG_64BIT |
12 | |
13 | /* |
14 | * Generic 32bit nops from GAS: |
15 | * |
16 | * 1: nop |
17 | * 2: movl %esi,%esi |
18 | * 3: leal 0x0(%esi),%esi |
19 | * 4: leal 0x0(%esi,%eiz,1),%esi |
20 | * 5: leal %ds:0x0(%esi,%eiz,1),%esi |
21 | * 6: leal 0x0(%esi),%esi |
22 | * 7: leal 0x0(%esi,%eiz,1),%esi |
23 | * 8: leal %ds:0x0(%esi,%eiz,1),%esi |
24 | * |
25 | * Except 5 and 8, which are DS prefixed 4 and 7 resp, where GAS would emit 2 |
26 | * nop instructions. |
27 | */ |
28 | #define BYTES_NOP1 0x90 |
29 | #define BYTES_NOP2 0x89,0xf6 |
30 | #define BYTES_NOP3 0x8d,0x76,0x00 |
31 | #define BYTES_NOP4 0x8d,0x74,0x26,0x00 |
32 | #define BYTES_NOP5 0x3e,BYTES_NOP4 |
33 | #define BYTES_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00 |
34 | #define BYTES_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00 |
35 | #define BYTES_NOP8 0x3e,BYTES_NOP7 |
36 | |
37 | #define ASM_NOP_MAX 8 |
38 | |
39 | #else |
40 | |
41 | /* |
42 | * Generic 64bit nops from GAS: |
43 | * |
44 | * 1: nop |
45 | * 2: osp nop |
46 | * 3: nopl (%eax) |
47 | * 4: nopl 0x00(%eax) |
48 | * 5: nopl 0x00(%eax,%eax,1) |
49 | * 6: osp nopl 0x00(%eax,%eax,1) |
50 | * 7: nopl 0x00000000(%eax) |
51 | * 8: nopl 0x00000000(%eax,%eax,1) |
52 | * 9: cs nopl 0x00000000(%eax,%eax,1) |
53 | * 10: osp cs nopl 0x00000000(%eax,%eax,1) |
54 | * 11: osp osp cs nopl 0x00000000(%eax,%eax,1) |
55 | */ |
56 | #define BYTES_NOP1 0x90 |
57 | #define BYTES_NOP2 0x66,BYTES_NOP1 |
58 | #define BYTES_NOP3 0x0f,0x1f,0x00 |
59 | #define BYTES_NOP4 0x0f,0x1f,0x40,0x00 |
60 | #define BYTES_NOP5 0x0f,0x1f,0x44,0x00,0x00 |
61 | #define BYTES_NOP6 0x66,BYTES_NOP5 |
62 | #define BYTES_NOP7 0x0f,0x1f,0x80,0x00,0x00,0x00,0x00 |
63 | #define BYTES_NOP8 0x0f,0x1f,0x84,0x00,0x00,0x00,0x00,0x00 |
64 | #define BYTES_NOP9 0x2e,BYTES_NOP8 |
65 | #define BYTES_NOP10 0x66,BYTES_NOP9 |
66 | #define BYTES_NOP11 0x66,BYTES_NOP10 |
67 | |
68 | #define ASM_NOP9 _ASM_BYTES(BYTES_NOP9) |
69 | #define ASM_NOP10 _ASM_BYTES(BYTES_NOP10) |
70 | #define ASM_NOP11 _ASM_BYTES(BYTES_NOP11) |
71 | |
72 | #define ASM_NOP_MAX 11 |
73 | |
74 | #endif /* CONFIG_64BIT */ |
75 | |
76 | #define ASM_NOP1 _ASM_BYTES(BYTES_NOP1) |
77 | #define ASM_NOP2 _ASM_BYTES(BYTES_NOP2) |
78 | #define ASM_NOP3 _ASM_BYTES(BYTES_NOP3) |
79 | #define ASM_NOP4 _ASM_BYTES(BYTES_NOP4) |
80 | #define ASM_NOP5 _ASM_BYTES(BYTES_NOP5) |
81 | #define ASM_NOP6 _ASM_BYTES(BYTES_NOP6) |
82 | #define ASM_NOP7 _ASM_BYTES(BYTES_NOP7) |
83 | #define ASM_NOP8 _ASM_BYTES(BYTES_NOP8) |
84 | |
85 | #ifndef __ASSEMBLY__ |
86 | extern const unsigned char * const x86_nops[]; |
87 | #endif |
88 | |
89 | #endif /* _ASM_X86_NOPS_H */ |
90 | |